Windows Action Center displays this error:
Restart to repair drive errors
We found errors on a drive. To repair these errors and prevent loss of data, restart your PC now. The repair could take a while to complete.
The restart completes (doing very rapid checks), and after a minute or so Action Center displays the same error again. This happens every time I start the computer. Sometimes the computer boots straight to the Start screen, and sometimes it boots to a blue screen with the option of sending a report to Microsoft before completing the boot. Sometimes it sends a report with no action required.
I have checked the hard drive using PC Checkup with MyDell, and with TuneUp Utilities, and no errors are reported. Using CHKDSK C: /f /r /x does not complete, but gets stuck at 13%.
I have also used chkdsk to check the two USB external drives that I use, and no errors are found.